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  •  » Weird....oil pressure issue

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    5/22/2020 9:54 AM  #1

    Bullet Bob
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    From: Montrose, Colorado
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    Weird....oil pressure issue

    I drove the Heap yesterday morning and on the way home I noticed NO OIL PRESSURE.  Hmmmm, not good.  Stopped, popped the hood, no mess, no bad noises, no apparent heating.  Drove it home real easy but noticed that the gauge came up about 1/4 at about 1300 rpm.
    Checked the gauge by the grounding test and It seems to be working normally.  Just installed a mechanical OP gauge and fired it up.  Gauge was bouncing (rapidly, in tune with RPM) from 40 to about 70 lbs on fire up at around 1200 rpm.  As it warmed and the idle fell off the fluctuating continues but the range kept dropping until it got to normal operating temperature (194) and idling at a steady 800 rpm.  At that point the range of bounces is from about 11 to 16 lbs.  The low pressure doesn't alarm me too much as I know the SBF idles at pretty low pressure.  My 90 Fox would almost take the gauge to zero at warm idle...had been doing that for it entire 150K miles.  Also, the Heap OP jumps  right up with the throttle so that's good, but what's with the jumping pressure?  I used this same gauge to verify pressure on the stand before I ever fired the engine and with the drill motor turning the pump pressure was rock steady.  Of course the turning parts have something to do with it but what, exactly. 
    I hate to but I keep thinking spun bearing except that should make some noise.  But then there is my crappy hearing also. 
    What do you think?

    BB1
     

    "you get what you pay for, good work isn't cheap, and there are NO free lunches...PERIOD!"
     

    5/22/2020 10:04 AM  #2

    TKOPerformance
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    From: Newark, DE
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    Re: Weird....oil pressure issue

    Pull the filter and cut it open and investigate.  If its a bearing you'll see evidence of it.  Oil can also be sent to someplace like Blackstone Labs for analysis and they will tell you if it has abnormally high levels of metal and what the metal is from. 
     

     

    5/22/2020 10:06 AM  #3

    RV6
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    From: Pine Junction, CO
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    Re: Weird....oil pressure issue

    I hate it when my oil pressure goes to zero.
    Something may have lodged itself in the pressure relief valve in the oil pump. This would suck as the pan would have to come off to check it.
    Pop the distributor out and spin the pump and see what the oil pressure does. I also have to agree cutting the filter open and peeling the pleats for a looksee is in order.
    Simple things first.

    Last edited by RV6 (5/22/2020 10:08 AM)

    Gary Zilik - Pine Junction, Colorado - 67 Coupe, 289-4V, T5
     

    5/22/2020 10:13 AM  #4

    Raymond_B
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    Re: Weird....oil pressure issue

    Yeah I kind of think it might be the relief spring/valve too.

    Cutting the filter is always a good idea to see what's going on. 

    Also pulling the dist to see the state of the drive gear and roll pin would be a really good idea.

     

    5/22/2020 10:51 AM  #5

    Bullet Bob
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    Re: Weird....oil pressure issue

    All good advice and I thank you all for that.  I also thought about the pressure relief valve.  I pressured up the sender with 70 psi air and got no gauge movement and infinity on the ohm meter so it does look like the sender died.  Butt (TS&T), how long has the fluctuating OP been going on?  The stock sender has a very small orifice and the gauge moves very slowly so it's doubtful it would report the fluctuating OP and that could have been going on for quite a while.
    I'll cut the filter and if that shows no issue I'll pull the dizzy and spin the pump....see what happens.
    Thanks again guys, I'll let you know.

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    "you get what you pay for, good work isn't cheap, and there are NO free lunches...PERIOD!"
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    5/22/2020 4:09 PM  #6

    6sally6
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    From: Surfside Beach,SC
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    Re: Weird....oil pressure issue

    Strange thangs happen to good folkz I guess?!
    You 'member a few months back my OP dropped to naught!
    Replaced the sender and 'it-was-healed'!!
      Funny thang......the orfice in the new one is tee-tiny compared to the old one. Now I have 'Shivel-lay' oil pressure!.
    Just so I got some......is the main thing I guess.
    Glad yours worked out fer-yee!
    6sal6

    Get busy Liv'in or get busy Die'n....Host of the 2020 Bash at the Beach/The only Bash that got cancelled  )8
     

    5/22/2020 8:57 PM  #7

    Nos681
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    From: Atlantic Mine, Michigan
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    Re: Weird....oil pressure issue

    From your description Bob sounds like the sending unit was intermittently working possibly giving you the appeared fluctuation in oil pressure
    Just my thought.

     

    5/23/2020 7:07 AM  #8

    Bullet Bob
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    Re: Weird....oil pressure issue

    Nos681 wrote:

    From your description Bob sounds like the sending unit was intermittently working possibly giving you the appeared fluctuation in oil pressure
    Just my thought.

    Actually Dan, the fluctuations weren't apparent on the stock sender/gauge.  I only saw that after I installed my old mechanical gauge to verify if it was the sender or a real loss of OP. 
    Glen at Steve's Mustang Parts said they had this fluctuation thing happen on the 331 in Steve's 67.  Turned out to be a bad filter.  So today I will work through the various potential causes:  Filter, stuck oil pump relief valve, something way worser. CarQuest says they are going to have a new sender for me this morning.  Also gonna grab a new filter.  With luck I'll know by noon if there is a 331 in Bob's immediate future.

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    "you get what you pay for, good work isn't cheap, and there are NO free lunches...PERIOD!"
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    5/23/2020 8:31 AM  #9

    TKOPerformance
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    Re: Weird....oil pressure issue

    Factory sender and gauge are really just a glorified idiot light.  I'd always trust what a mechanical gauge says vs. the factory gauge. 

     

    5/23/2020 1:29 PM  #10

    Bullet Bob
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    Re: Weird....oil pressure issue

    TKOPerformance wrote:

    Factory sender and gauge are really just a glorified idiot light.  I'd always trust what a mechanical gauge says vs. the factory gauge. 

    I agree Tom but I really don't want to make a change to a "modren cluster" 

    But, while I'm here I may as well give an update.

    I ain't lookin' good.  I replaced the filter to eliminate that posibility...no joy.  I pulled the distributor and spun the pump....intant steady 70 lbs on the same gauge that was showing the flutter so that should eliminate the possible stuck relief valve.
    Tomorrow morning I'll cut the filter and see what's in there (if anything) then pull the pan and start digging deeper.  It acts like a large open/closed internal leak with the pressure jumping as much as it is.  I can think of a couple of things that maybe could do that...and ain't none of 'em good.

    More to follow.

    BB1

    "you get what you pay for, good work isn't cheap, and there are NO free lunches...PERIOD!"
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    5/23/2020 3:22 PM  #11

    BobE
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    Re: Weird....oil pressure issue

    BB - could the hex drive in the distributor be degrading and slipping?

    65 Fastback, 351W, 5-speed, 4 wheel discs, 9" rear,  R&C Front End.
     

    5/23/2020 3:53 PM  #12

    50vert
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    Re: Weird....oil pressure issue

    When you pull the pan, look for a crack in the pick-up tube.

    "Those telephone poles were like a picket fence"
     

    5/23/2020 4:17 PM  #13

    RV6
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    Re: Weird....oil pressure issue

    Bullet Bob wrote:

    TKOPerformance wrote:

    Factory sender and gauge are really just a glorified idiot light.  I'd always trust what a mechanical gauge says vs. the factory gauge. 

    I agree Tom but I really don't want to make a change to a "modren cluster" 

    But, while I'm here I may as well give an update.

    I ain't lookin' good.  I replaced the filter to eliminate that posibility...no joy.  I pulled the distributor and spun the pump....intant steady 70 lbs on the same gauge that was showing the flutter so that should eliminate the possible stuck relief valve.
    Tomorrow morning I'll cut the filter and see what's in there (if anything) then pull the pan and start digging deeper.  It acts like a large open/closed internal leak with the pressure jumping as much as it is.  I can think of a couple of things that maybe could do that...and ain't none of 'em good.

    More to follow.

    BB1

    Well this really suck large time! Just like you, the only thing I can think of that could have an open/closed leak is also not good. Keeping my fingers cross though.

    I did manage to put 200 miles on the 67 this morning. Due to weather and Covid this morning was the first match I have been able to shoot since October. Even being rusty I was pleased with my shooting.
     

    Gary Zilik - Pine Junction, Colorado - 67 Coupe, 289-4V, T5
     

    5/23/2020 4:19 PM  #14

    TKOPerformance
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    Re: Weird....oil pressure issue

    Am I correct in thinking that the pressure starts jumping around only after its warmed up? 

     

    5/23/2020 4:21 PM  #15

    Bullet Bob
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    Re: Weird....oil pressure issue

    BobE:  I'll check that first in the AM, thanks.

    Barry:  I'll check that first if BobE's suggestion doesn't probe anything.  Thanks.  Also, since I know your are interested.  I got the fuel very close to perfect at WOT by adding 9% fuel.  The hot start issue is solved...I reduced the warm crank pulse to .33 ms per Decipha suggestions.  I had it at the calculated value but apparently with those injectors you gotta cut it down quite a bit more when warm.
    Idle/stalling is next unless I'm building a 331, then I'll have to start over.

    BB1

    "you get what you pay for, good work isn't cheap, and there are NO free lunches...PERIOD!"
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    5/23/2020 4:24 PM  #16

    Bullet Bob
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    Re: Weird....oil pressure issue

    TKOPerformance wrote:

    Am I correct in thinking that the pressure starts jumping around only after its warmed up? 

    No Tom, it starts fluctuating from around 40 to 70 upon cold start.  I'm thinking rotating assy since the frequency seems to follow the rpm as the engine warms and the fluctuation gets smaller with the normal drop in OP as the engine warms.  I'll be we know more by this time tomorrow.

    BB1
     

    "you get what you pay for, good work isn't cheap, and there are NO free lunches...PERIOD!"
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    5/23/2020 4:28 PM  #17

    Bullet Bob
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    Re: Weird....oil pressure issue

    Gary;  Happy to hear you got to cruise the 67.  Hope it's working well after all the time you spent on it over the extended winter.  As for the shooting, I don't want to hear about it...haven't been out for months but I got a lot of ammo loaded.

    BB1

    "you get what you pay for, good work isn't cheap, and there are NO free lunches...PERIOD!"
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    5/23/2020 5:05 PM  #18

    50vert
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    Re: Weird....oil pressure issue

    It sounds like you're really getting a handle on the tuning, great news!
    All the ranges have been closed here, and I haven't done the required amount of comps to keep my license ... or my guns.  Hoping they'll make an exception.

    "Those telephone poles were like a picket fence"
     

    5/23/2020 8:57 PM  #19

    Bullet Bob
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    Re: Weird....oil pressure issue

    Been noodling this and I'll tell you what I think it is....the only thing I can come up with that could make the OP behave like this.....Ready?

    I think it has a loose main bearing cap.  Wouldn't have to be very loose to make the OP turn on and off.  That's my entry.  Let you know tomorrow.

    BB1
     

    "you get what you pay for, good work isn't cheap, and there are NO free lunches...PERIOD!"
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    5/23/2020 8:59 PM  #20

    6sally6
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    From: Surfside Beach,SC
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    Re: Weird....oil pressure issue

    What's the old expression......"boxing-with-shadows"?!  I think...it's just being a FORD!. The key thing so far is.....no noise. Until you hear(and you will!) strange ticking/grinding/rattling..........don't sweat it.
    Buddy of mine (another buddy!) once said he uses the oil pressure light as a shift light..........when it  started slightly blinking he was JUST ABOUT to his shift point. Once the oil light burned bright red he knew it was time to go to 3rd gear!!
    6sal6

    Get busy Liv'in or get busy Die'n....Host of the 2020 Bash at the Beach/The only Bash that got cancelled  )8
     

    5/24/2020 5:53 AM  #21

    TKOPerformance
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    Re: Weird....oil pressure issue

    Nah, pull the pan.  Once it starts making noise something's hurt.  Not worth it, when a once over now could easily fix something before it becomes an issue. 

    I'd check every bearing and the torque on every fastener.  Pull the pump, disassemble it and go through it looking for gouges, play, etc. 

    I'd check all the bolts on the oil pump too.  On my 331 I drilled an safety wired the pump to block and pickup to pump bolts just to be safe.

     

    5/24/2020 8:19 AM  #22

    John Ha
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    Re: Weird....oil pressure issue

    I wonder if something might have gotten stuck in the passage that feeds the oil pressure sender/gauge.  Is there a way that you could crank the engine without an oil pressure sender attached to see if anything other than oil comes out?  I know I scared the @#!! out of myself a couple of times when stuff obstructed the sender and the oil pressure did strange things.

    Founding Member of the Perpetually Bewildered Society
     

    5/24/2020 8:30 AM  #23

    TKOPerformance
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    Re: Weird....oil pressure issue

    Pull the stalk, clean it and blow through it.  You could connect a hose to a catch can at the stalk or the block with an NPT to nipple fitting and a piece of 3/8" hose. 

     

    5/24/2020 9:23 AM  #24

    Raymond_B
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    Re: Weird....oil pressure issue

    So the drive gear and roll pin look fine? I know you said you pulled the dist, but I didn't see where you said what condition it's in.

     

    5/24/2020 9:35 AM  #25

    red351
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    Re: Weird....oil pressure issue

    Maybe a crack in the crank before it completely breaks apart.

     

     

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